کربلایی
مدیر بازنشسته
سلام
در این تاپیک، متونی زبان اصلی و مفید برای رشته فناوری اطلاعات رو قرار میدیم تا دوستان بصورت گروهی و پاراگراف به پارگراف اون ها رو ترجمه کنند.
بدین صورت علاوه بر بهتر شدن قدرت خواندن متون اصلی، مطالب جدیدی هم یاد میگیریم
کار رو با کتاب INFORMATION RESOURCE GUIDE
Computer, Internet and Network Systems Security
آغاز میکنیم:
اگر دوستان استقبال کنند، بیه کتاب رو هم قدم به قدم میزارم تا ترجمه کنیم، من این کتاب رو به همه اونایی که میخوان درباره امنیت شبکه های کامپیوتری بیشتر بدونند توصیه می کنم
در این تاپیک، متونی زبان اصلی و مفید برای رشته فناوری اطلاعات رو قرار میدیم تا دوستان بصورت گروهی و پاراگراف به پارگراف اون ها رو ترجمه کنند.
بدین صورت علاوه بر بهتر شدن قدرت خواندن متون اصلی، مطالب جدیدی هم یاد میگیریم
کار رو با کتاب INFORMATION RESOURCE GUIDE
Computer, Internet and Network Systems Security
آغاز میکنیم:
اگر دوستان استقبال کنند، بیه کتاب رو هم قدم به قدم میزارم تا ترجمه کنیم، من این کتاب رو به همه اونایی که میخوان درباره امنیت شبکه های کامپیوتری بیشتر بدونند توصیه می کنم
1.0Introduction
1.1 Basic Internet Technical Details
The Internet utilizes a set of networking protocols called TCP/IP. The applications protocols that can be used with TCP/IP are described in a set of Internet Engineering Task Force (IETF) RFCs (Request For Comment). These documents describe the "standard" protocols and applications that have been developed to support these protocols. Protocols provide a standard method for passing messages. They define the message formats and how to handle error conditions. Protocols are independent of vendor network hardware, this allows communication between various networks with different hardware as long as they communicate (understand) the same protocol. The following diagram provides a conceptual layering diagram of the protocols.
1.1.1 TCP/IP : Transmission Control Protocol/Internet Protocol
TCP/IP is used to facilitate communication within a network of diverse hardware technology. Information is broken into packets (usually in the range of 1-1500 characters long) to prevent monopolizing of the network. TCP is a transport level protocol which allows a process on one computer to send data to a process on another computer. It is a connection oriented protocol which means that a path must be established between the two computers. IP defines the datagram, the format of the data being transferred throughout the network and performs connectionless delivery.
Connectionless delivery requires each datagram to contain the source and destination address and each datagram is processed separately. TCP takes the information, and breaks it into pieces called packets, numbers the packets, and then sends them. The receiving computer collects the packets, takes out the data and puts them in the proper order. If something is missing, the receiving computer asks the sender to retransmit. The packet sent also contains a checksum which is used to find errors that may have occurred during transmission. If the receiving computer notices that an error has occurred when it computes and compares the checksum, it throws that packet away and asks for a retransmission. Once everything is received, the data is passed to the proper application (e.g. email).
1.1.2 UDP:User Datagram Protocol
The UDP has less overhead and is simpler than TCP. The concept is basically the same except that UDP is not concerned about lost packets or keeping things in order. It is used for short messages. If it does not receive a response, it just resends the request. Thjs type of protocol transfer method is called a “connectionless protocol.”
1.1.3 Internet Addressing
All computers on the Internet must have a distinct network address to be able to efficiently communicate with each other. The addressing scheme used within the Internet is a 32 - bit address segmented into a hierarchical structure. IP addresses consist of four numbers, each less than 256 which are separated by periods.
(#.#.#.#) At the lowest level, computers communicate with each other using a hardware address (on LANs, this is called the Medium Access Control or MAC address). Computer users, however, deal with 2 higher levels of abstraction in order to help visualize and remember computers within the network. The first level of abstraction is the IP address of the computer (e.g. 131.136.196.2) and the second level is the human readable form of this address (e.g. manitou.cse.dnd.ca). This address scheme is currently under review as the address space is running out. Address Resolution Protocol (ARP) can be used by the computer to resolve IP addresses into the corresponding hardware addresses.
1.1 Basic Internet Technical Details
The Internet utilizes a set of networking protocols called TCP/IP. The applications protocols that can be used with TCP/IP are described in a set of Internet Engineering Task Force (IETF) RFCs (Request For Comment). These documents describe the "standard" protocols and applications that have been developed to support these protocols. Protocols provide a standard method for passing messages. They define the message formats and how to handle error conditions. Protocols are independent of vendor network hardware, this allows communication between various networks with different hardware as long as they communicate (understand) the same protocol. The following diagram provides a conceptual layering diagram of the protocols.
1.1.1 TCP/IP : Transmission Control Protocol/Internet Protocol
TCP/IP is used to facilitate communication within a network of diverse hardware technology. Information is broken into packets (usually in the range of 1-1500 characters long) to prevent monopolizing of the network. TCP is a transport level protocol which allows a process on one computer to send data to a process on another computer. It is a connection oriented protocol which means that a path must be established between the two computers. IP defines the datagram, the format of the data being transferred throughout the network and performs connectionless delivery.
Connectionless delivery requires each datagram to contain the source and destination address and each datagram is processed separately. TCP takes the information, and breaks it into pieces called packets, numbers the packets, and then sends them. The receiving computer collects the packets, takes out the data and puts them in the proper order. If something is missing, the receiving computer asks the sender to retransmit. The packet sent also contains a checksum which is used to find errors that may have occurred during transmission. If the receiving computer notices that an error has occurred when it computes and compares the checksum, it throws that packet away and asks for a retransmission. Once everything is received, the data is passed to the proper application (e.g. email).
1.1.2 UDP:User Datagram Protocol
The UDP has less overhead and is simpler than TCP. The concept is basically the same except that UDP is not concerned about lost packets or keeping things in order. It is used for short messages. If it does not receive a response, it just resends the request. Thjs type of protocol transfer method is called a “connectionless protocol.”
1.1.3 Internet Addressing
All computers on the Internet must have a distinct network address to be able to efficiently communicate with each other. The addressing scheme used within the Internet is a 32 - bit address segmented into a hierarchical structure. IP addresses consist of four numbers, each less than 256 which are separated by periods.
(#.#.#.#) At the lowest level, computers communicate with each other using a hardware address (on LANs, this is called the Medium Access Control or MAC address). Computer users, however, deal with 2 higher levels of abstraction in order to help visualize and remember computers within the network. The first level of abstraction is the IP address of the computer (e.g. 131.136.196.2) and the second level is the human readable form of this address (e.g. manitou.cse.dnd.ca). This address scheme is currently under review as the address space is running out. Address Resolution Protocol (ARP) can be used by the computer to resolve IP addresses into the corresponding hardware addresses.
